Signal distribution structure and method for distributing a signal

Abstract

A signal distribution structure for distributing a signal to a plurality of devices includes a first signal guiding structure including a first characteristic impedance. The signal distribution structure also includes a node, wherein the first signal guiding structure is coupled to the node. The signal distribution structure includes a second signal guiding structure including one or more transmission lines. The one or more transmission lines of the second signal guiding structure are coupled between the node and a plurality of device connections. The second signal guiding structure includes, side-viewed from the node, a second characteristic impedance which is lower than the first characteristic impedance. The signal guiding structure also includes a matching element connected to the node.

The invention claimed is: 
     
       1. A signal distribution structure for distributing a signal to a plurality of device connections, the signal distribution structure comprising:
 a first signal guiding structure comprising a first characteristic impedance; 
 a node, wherein a first transmission line of the first signal guiding structure is coupled to the node; 
 a second signal guiding structure comprising one or more transmission lines circuited between the node and a branch point, 
 wherein the one or more transmission lines of the second signal guiding structure are coupled between the node and the plurality of device connections, and 
 wherein the second signal guiding structure comprises, side-viewed from the node, a second characteristic impedance which is lower than the first characteristic impedance; and 
 a matching element connected to the node; 
 wherein the matching element is configured to match an impedance at the node, side-viewed from the second signal guiding structure, to the second impedance, and to increase a mismatch between an impedance at the node, side-viewed from the first signal guiding structure, and the first impedance; and 
 a plurality of Y-sharing branches branching from the branch point, 
 wherein impedances of the single Y-sharing branches deviate from the impedance of the first signal guiding structure by no more than 30% of the impedance of the first signal guiding structure, and 
 wherein the impedance of the second signal guiding structure is matched to a joint impedance of the Y-sharing branches, such that the impedance of the second signal guiding structure is smaller than the impedance of the first signal guiding structure. 
 
     
     
       2. The signal distribution structure according to  claim 1 , wherein the second signal guiding structure comprises a single second transmission line. 
     
     
       3. The signal distribution structure according to  claim 1 , wherein the first impedance is within a range between 30Ω and 70Ω. 
     
     
       4. The signal distribution structure according to  claim 1 , wherein the impedances of the Y-sharing branches are within a range between 30 Ohm and 70 Ohm. 
     
     
       5. The signal distribution structure according to  claim 1 , wherein the matching element comprises a resistor connected to the node. 
     
     
       6. The signal distribution structure according to  claim 1 , wherein the matching element is connected between the node and a constant-potential node. 
     
     
       7. The signal distribution structure according to  claim 1 , wherein the matching element is connected between the node and a power supply configured to bias the node. 
     
     
       8. The signal distribution structure according, to  claim 1 , wherein the first signal guiding structure, the node, the second signal guiding structure and the device connection are arranged on a device-under-test board for usage in a device tester. 
     
     
       9. The signal distribution structure according to  claim 1 , wherein the first transmission line of the first signal guiding structure is coupled to the node via a connection element of the first signal guiding structure. 
     
     
       10. The signal distribution structure according to  claim 9 , wherein the connection element comprises a via coupled to the node and a pin coupled to the first transmission line, wherein the pin is arranged to detachably contact the via. 
     
     
       11. The signal distribution structure according to  claim 9 , wherein the node and the second transmission structure are arranged on a device-under-test board. 
     
     
       12. The signal distribution structure according, to  claim 1 , wherein the signal distribution structure comprises a matched driver;
 wherein the first transmission line is circuited between an output of the matched driver and the node; and 
 wherein an output impedance of the matched driver is matched to an impedance of the first transmission line. 
 
     
     
       13. The signal distribution structure according to  claim 1 , wherein the impedance of the first signal guiding structure is in the range between 40 Ohm and 60 Ohm. 
     
     
       14. The signal distribution structure according to  claim 1 , wherein the signal distribution structure is configured to provide a common input signal generated by a driver to a plurality of devices via the first signal guiding structure via the node and via the second signal guiding structure. 
     
     
       15. The signal distribution structure according to  claim 1 , wherein the signal distribution structure is configured such that a reflected signal, traveling towards the node via the second signal guiding structure, is absorbed in the matching element, or in a termination of the first signal guiding structure. 
     
     
       16. A signal distribution structure for distributing a signal to a plurality of device connections, the signal distribution structure comprising:
 a first signal guiding structure comprising a first characteristic impedance; 
 a node, wherein a first transmission line of the first signal guiding structure is coupled to the node; 
 a second signal guiding structure comprising one or more transmission lines and a plurality of Y-sharing branches; 
 wherein the one or more transmission lines of the second signal guiding structure are coupled between the node and the plurality of device connections, 
 wherein the second signal guiding structure comprises, side-viewed from the node, a second characteristic impedance which is lower than the first characteristic impedance; 
 wherein the plurality of Y-sharing branches are connected to the node; and 
 wherein a joint impedance of the Y-sharing branches, side-viewed from the node, is smaller than the impedance of the first transmission line; and 
 a matching element connected to the node; 
 wherein the matching element is configured to match an impedance at the node, side-viewed from the second signal guiding structure, to the second impedance, and to increase a mismatch between an impedance at the node, side-viewed from the first signal guiding structure, and the first impedance. 
 
     
     
       17. The signal distribution structure according to  claim 16 , wherein the impedance of the first transmission line is within a range between 30Ω and 70Ω; and
 wherein impedances of the single Y-sharing branches are within a range between 30Ω and 70Ω. 
 
     
     
       18. The signal distribution structure according to  claim 16 , wherein the impedances of the single Y-sharing branches deviate from the impedance of the first transmission tine by no more than 30% of the impedance of the first transmission line. 
     
     
       19. A signal distribution structure for distributing a signal to a plurality of device connections, the signal distribution structure comprising:
 a first signal guiding structure comprising a first characteristic impedance; 
 a node, wherein the first signal guiding structure is coupled to the node; 
 a second signal guiding structure comprising one or more transmission lines, 
 wherein the one or more transmission lines of the second signal guiding structure are coupled between the node and the plurality of device connections, and 
 wherein the second signal guiding structure comprises, side-viewed from the node, a second characteristic impedance which is lower than the first characteristic impedance; and 
 a matching element connected to the node; 
 wherein the matching clement is configured to match an impedance at the node, side-viewed from the second signal guiding structure, to the second impedance, and to increase a mismatch between an impedance at the node, side-viewed from the first signal guiding structure, and the first impedance; and 
 wherein the node is formed using a branch via extending vertically through a multi-layer printed circuit hoard, and using a signal splitting structure, 
 wherein the first signal guiding structure is coupled to a first end of the branch via, 
 wherein the matching element is coupled to a second end of the branch via, 
 wherein the signal splitting structure is formed in a conductive layer of the multi-layer printed circuit board, 
 wherein the signal splitting structure is coupled to the branch via between the first end of the branch via and the second end of the branch via, and 
 wherein the signal splitting structure is configured to spread the signal from the via to a plurality of branch transmission lines. 
 
     
     
       20. The signal distribution structure according to  claim 19 ,
 wherein a first of the branch transmission lines and a second of the branch transmission lines are arranged on different layers of the multi-layer print circuit board, 
 wherein the signal splitting structure is arranged on another layer of the multi-layer printed circuit board, which other layer is arranged between the layers in which the branch transmission lines are routed. 
 
     
     
       21. The signal distribution structure according to  claim 20 ,
 wherein the first branch transmission line and the second branch transmission line are coupled to the signal splitting structure using vias extending through the multi-layer printed circuit board.